Spiral wound gasket thickness and flange groove depth

[PV design Engr]

I have a horizontal vessel and on which a tower is mounted. The tower mounting flange is a male female type app-2 designed flange. The flange on the horizontal vessel is female type with groove depth of 5 mm. The raised face in male type flange is 5mm. We have used 4.5mm thick spiral wound gasket in this case. Flange ID is 1700mm. Manufacturer by mistake has procured 6.35 mm thick gasket. The equipment has to be hydrotested next week. Can i accept 6.35 mm thickness gasket for 5 mm grove considering that fact that the gasket in compressed state will be aroud 4.5mm. Does any one has previois experience on this issue

 

[r6155]

Check calculations.

Regards

 

[PV design Engr]

Thickness do not have any impact on flange design nevertheless checked and no issue.

 

[r6155]

The recommended compressed thickness is what experience has indicated to be the optimum range in order to
achieve maximum resiliency of the gasket

Gasket 6,4mm should be compressed to 4,8 mm(recommended) with a 4,8mm guide ring

The gasket can be overloaded, even without excessive bolt stress. The full initial bolt load is imposed entirely on the gasket, unless the gasket has a stop ring or the flange face detail is arranged to provide the equivalent. Without such means of controlling the compression of the gasket, consideration must be given to the selection of gasket type, size and material that will prevent gross crushing of the gasket.

Factor m=3 is recommended : See Flexitallic Gasket Design Criteria

Values of m, b and y in ASME VIII Div.1 Mandatory Appendix 2 are suggested only and are not mandatory. Also see Appendix S.

The Above mentioned is part of calculation.

Regards

 

[r6155]

To ensure greater gasket stability, for larger diameters above 39” (1000 mm) Flexitallic recommend
0.285 in (7.2 mm) thick gasekts with 0.197 in (5.0 mm) thick guide rings, or 0.250 in (6.4 mm) thick gaskets with 0.188 in
(4.8 mm) thick guide rings.

External loads (wind, seismic, weight of column, etc, ) were considered in design of flange to avoid leakage?.

Regards

 

[SnTMan]

PV design Engr, functionally I'd think you'd be OK, subject to a few things:

1) I'd hope you have a compression ring
2) Is the gasket for hydro only or is it to remain installed. If the latter:
- a) Are overall critical dimensions acceptable?
- b) Does the owner approve?

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand